This invention relates generally to improvements in weaving looms to provide for satisfactory weaving of fabric of selected widths that may be substantially less than the total width of the loom. More specifically, the invention relates to an improvement in such looms providing for selective positioning of the shuttle mechanism or mechanisms at various locations along the shuttle raceway.
In recent year numerous advances in weaving technology and in the construction of large, heavy duty looms has permitted the weaving of fabrics, including heavy fabrics, in ever increasing widths. Looms are now available and in use in various weaving industries, such as those relating to the weaving of papermaking fabrics, that are capable of weaving fabric of 30 meters or more in width and of indefinite length. Because of the massive size and the great strength required for the various components of such a loom, these very large looms are extremely expensive, sometimes costing many hundreds of thousands of dollars. Accordingly, it is important to have such looms in operation, producing salable fabric, to the greatest extent possible. Because only certain customers have requirements for as wide as the largest of these looms, it has been difficult to use such looms to their full capacity. The nature of weaving limits the ability of such large looms to weave fabrics substantially narrower than the total width of the loom. This is because the shuttle pulling the weft filaments back and forth across the raceway of the loom must maintain substantial tension on that weft filament at all times to provide a consistently high quality fabric. However, if weaving of a fabric substantially narrower than the total width of the loom is attempted, at each reversal of the shuttle's movement, there is a brief period when the weft goes slack, thus increasing the potential for unsatisfactory weaves.
In known looms there has been little that can be done about this problem because of the massive apparatus that is needed to support and move the shuttle box assembly, which has required that the shuttle box assemblies remain positioned adjacent the extreme ends of the loom. Thus, the very largest and most expensive looms frequently experience the lowest rates of utilization in a weaving mill.